Re: [gentoo-user] Failure to start md at boot

[Peter Humphrey <peter@prh.myzen.co.uk>]

On Sunday 31 May 2015 13:06:58 Mick wrote:
> On Sunday 31 May 2015 10:01:43 Peter Humphrey wrote:
> > On Friday 29 May 2015 01:10:52 I wrote:
> > > OK, so this is what I have at present. I haven't booted with it yet to
> > > test it - I'll do that in the morning:
> > > 
> > > DEVICE /dev/sd[abcde][123456789]
> > > ARRAY /dev/md1 UUID=ea156c7f:183ca28e:c44c77eb:7ee19756
> > > ARRAY /dev/md5 UUID=e7640378:966a5b3a:c44c77eb:7ee19756
> > > ARRAY /dev/md7 UUID=c2d056c4:9118021f:ad73c633:b38fa97c
> > 
> > Specifying the UUIDs hasn't helped. I still get failure to start /dev/md7
> > during boot as often as not.
> 
> Did you try my suggestion to (also) specify the metadata type to see if it
> makes a difference?

Ah, no, I missed that. I'll try it and see how it goes.

> Something else to check:
> 
> Make sure that the /etc/fstab name for the RAID device and your
> /etc/mdadm.conf use the same name.

Yes, they're the same - but fstab isn't consulted until long after the VGs are 
started, is it?

> If you have changed the partitions on this RAID, or recreated it, make sure
> to run 'mdadm --zero-superblock', before you delete the partition from the
> partition table, or you could recover it when you recreate a partition if
> not zeroed.

Nope, haven't changed anything since creation.

> Have a look at smartctl output to see if there is something wrong with any
> of the md7 disks.

I was suspicious of the spinning disks I've just replaced with SSDs, because 
they were showing a few errors and not a lot of remaining life. Smartctl 
doesn't recognise the SSDs so I don't know how useful its output is, but it's 
not reporting anything anyway.

-- 
Rgds
Peter